How Do You Calculate Linear Drag Coefficient for Spherical Objects in Flight?

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Screwdriver
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I'm trying to model the flight of a small spherical object (such as a ping-pong ball) through air at smallish velocities ([itex]\approx 5{_{m/s}}[/itex]) with linear drag so that [itex]F_{d}=-bv[/itex]. The problem is, I can't find a table of linear drag coefficients ([itex]b[/itex]) anywhere; it's always just the normal drag coefficient [itex]C_{d}[/itex] which is for when the drag force is proportional to [itex]v^2[/itex]. I don't think you can just use [itex]C_{d}=b[/itex] since they have different units.

However, I came across this, which I think is saying that [itex]b=6\pi \mu R[/itex], which would be good since I could look up [itex]\mu[/itex] from say, here. Does that seem like a good idea?
 
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Well, 5m/s is not a speed at which a linear drag occurs.
To be sure of it, see that general curve :
https://commons.wikimedia.org/wiki/File:CX_SPHERE.png

But if you really wanted (I'm afraid it's too late) to calculate the flight of a sphere with a linear drag, I published recently these two tables of linear drag coefficients :
https://commons.wikimedia.org/wiki/...e_quelques_particules_en_Régime_de_Stokes.png
https://commons.wikimedia.org/wiki/File:Tableau_cx_lineaires_deuxieme.png

Friendly, Bernard of Go Mars